code: def test_libtpu_init_args(self):
      if jtu.is_device_tpu(version=4):
          raise unittest.SkipTest("TODO(b/240151176)")
  
      computation = (
          jax.jit(lambda x, y: x + y).lower(1, 1).compiler_ir()
      )
      devices = np.array([[jax.local_devices()[0]]])
      compile_options = compiler.get_compile_options(
          num_replicas=1, num_partitions=1
      )
      backend = xla_bridge.get_backend()
  
      orig_libtpu_init_args = os.getenv("LIBTPU_INIT_ARGS")
      orig_argv = sys.argv
      try:
          os.environ[
              "LIBTPU_INIT_ARGS"
          ] = "--xla_spmd_threshold_for_windowed_einsum_mib=0"
          key1 = cache_key.get(
              computation, devices, compile_options, backend
          )
          os.environ[
              "LIBTPU_INIT_ARGS"
          ] = "--xla_spmd_threshold_for_windowed_einsum_mib=1"
          key2 = cache_key.get(
              computation, devices, compile_options, backend
          )
          self.assertNotEqual(key1, key2)
  
      finally:
          if orig_libtpu_init_args is not None:
              os.environ["LIBTPU_INIT_ARGS"] = orig_libtpu_init_args
          elif os.getenv("LIBTPU_INIT_ARGS") is not None:
              del os.environ["LIBTPU_INIT_ARGS"]
          sys.argv = orig_argv
  
imports: import hashlib
  import os
  import sys
  import unittest
  import numpy
  from absl.testing import absltest
  from absl.testing import parameterized
  import jax
  from jax import lax
  from jax._src import cache_key
  from jax._src import compiler
  from jax._src import config
  from jax._src import test_util
  from jax._src import xla_bridge
  from jax._src.lib import xla_client
  from jax._src.lib import xla_extension_version
label_desc: Use image node_id 10 for calling the CacheKeyTest obj's underlying member method code with example usage: obj.test_libtpu_init_args() without return types